In distribution centers, the use of automated Storage and Retrieval Machines (SRM) to handle palletized unit loads in a warehouse setting is well known. In a typical facility, the palletized unit loads are stored on one side of a lane by an SRM which typically has a multi-story crane that moves along each lane of the warehouse. The SRM includes an automated forklift apparatus that moves along the length of the crane and moves the various palletized unit loads around the warehouse. Typically, the SRM may store palletized unit loads on one side of a lane having multiple stories of storage space and then retrieved and positioned by the SRM on the opposite side of the lane for distribution of the palletized unit load. In this storage and distribution process, the SRM travels back and forth along the lane either storing or retrieving palletized unit loads from different levels of the warehouse. It is quite common for the pallet and/or the unit load to become repositioned or poorly staged during the storage and retrieval process due to mechanical machine failure or from human intervention in which the pallet or unit load is brought into direct interference with the travel path of the SRM, thereby resulting in the SRM colliding with the pallet or unit load during the normal travel cycle and operation of the SRM. Such collisions can cause severe damage to the SRM. As such, there is a need for a crash prevention system that prevents collisions between the SRM and the obstruction.